1. Field
Embodiments relate to a secondary battery.
2. Description of the Related Art
In general, a secondary battery refers to a battery which is chargeable and dischargeable. A secondary battery may be widely used for small high-tech electronic devices such as a mobile phone, a personal digital assistant (PDA), and a laptop computer. A lithium ion secondary battery may have an operation voltage of, e.g., 3.6V, which is about 3 times as much as that of a nickel-cadmium battery and a nickel-hydrogen battery generally used for a power source of electronic equipments. Also, since the lithium ion secondary battery has a high energy density per unit weight, use of the lithium ion secondary battery is rapidly increasing. The lithium ion secondary battery may use a lithium-based oxide for an anode active material and a carbon for a cathode active material.
The lithium ion secondary battery is manufactured in various shapes such as a cylinder shape, a polygonal column or prismatic shape, a pouch shape, etc. The pouch-type secondary battery may include an electrode assembly and a pouch-type case receiving the electrode assembly.